- Health Effects - Exposure assessment, and the effects of measurement error on epidemiological analysis.
- Urban and Regional Smog - Characterization of atmospheric transport and transformation; attribution of particulate matter to sources; characterization of measurement quality.
- Visibility Degradation - Theoretical analysis of radiative transfer and particle optics; analysis of haze composition data; assessment of monitoring and regulatory strategies.
- Global Climate Change - Radiative effects and remote sensing of particles.
My current research centers on the analysis and quality-assurance of data from the IMPROVE network (Interagency Monitoring of PROtected Visual Environments) operated for the National Park Service by the Air Quality Research Center. I also retain earlier interests in all aspects of atmospheric visibility, and in qualitative analyses of the equation systems governing particle coagulation and tropospheric photochemistry.